A wireless communication system supports mobility of an MS using handover. For example, the MS selects a target BS from among neighbor BSs of a serving BS when the MS performs handover. After, the MS releases from the serving BS and connects to the target BS.
As described above, an MS releases from a serving BS and connects to a target BS for handover. Therefore, there occurs data loss because the MS is disconnected from both the serving BS and the target BS temporarily.
In order to solve this problem, a serving BS temporarily stores data to be transmitted to an MS when the serving BS releases from the MS. The serving BS reduces data loss for the MS incurred during handover by transmitting stored data for the MS to the target BS when the MS connects to the target BS. Herein, the serving BS transmits data to the target BS via a backhaul. Hereinafter, it is assumed that stored data to be transmitted to the MS in the serving BS is referred to as handover data.
The serving BS transmits the handover data to the target BS as soon as MS is connected to the target BS.
However, the handover data transmitted from the serving BS may be lost, and transmission time delay may occur due to a congested situation when a backhaul capacity is limited or an available backhaul capacity is not enough.
Therefore, there is a need to provide an improved method and apparatus for solving the above problem.